


Quicksand

by writergirl8



Category: Teen Wolf (TV)
Genre: F/M, Step-Sibling Incest, Step-siblings
Language: English
Status: Completed
Published: 2015-11-09
Updated: 2015-11-09
Packaged: 2018-04-30 21:15:27
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,896
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5179973
Author URL: https://archiveofourown.org/users/writergirl8/pseuds/writergirl8
Summary: <blockquote class="userstuff">
              <p>Stiles is starting to realize, looking at all these variables compiling up at once, that there is no way they can keep this up forever. Someday, the cards are going to fall. Looking over at Lydia, he wonders where they’re going to land, and what’s going to be left when the two of them finally go up in smoke.</p>
            </blockquote>





	Quicksand

**Author's Note:**

> This started off as a request from [Stilestilikeslydia](http://stilestilikeslydia.tumblr.com) on tumblr, but when I started really thinking about the universe I wanted to put into it, I couldn't let it go! So, just a fair warning, there's a sex scene between step-siblings, but the story aligns with canon in that Stiles has liked Lydia since the third grade. Suggested listening for this one is Have You Ever Needed Someone So Bad by Def Leppard and Treacherous by Taylor Swift. They fit this really beautifully. Shout out to [blackjacktheboss](http://blackjacktheboss.tumblr.com) for sticking with me on this from top to bottom. If you want to talk Stydia, I am [rongasm](http://rongasm.tumblr.com) on tumblr.

They decide on Facetime, the night before, that Stiles isn't going to come pick Lydia up at the airport.

"It would be too obvious," she had said, peering down into the camera of her laptop as she moves around her dorm room, meticulously packing the last of her things. "And if you volunteering to take the trip isn't obvious enough, the rest of you is also about as subtle as a gun."

Stiles had leaned back in his desk chair and pulls an annoyed face.

"So you're just going to have me send your mom to pick you up all by her lonesome?"

"Your dad can come with her."

"Nah, he has a shift."

"I'll be with her," Lydia had told him finally. "Seriously, Stiles, just stay at home."

Which is why he's sitting on his bed with his whole body tensed, watching the driveway and waiting for the familiar headlights of Natalie's car to appear on his windowpane. The fact that Lydia Martin is only a few minutes away from him is even more maddening than having a six hour flight between them. The worst part is knowing that it's going to be even more difficult once she actually gets here.

"STILES!" shouts his dad from the kitchen. He'd gotten home at six exactly so that he could be here for family dinner, a fact that had frustrated Stiles to no end, because it means that they have not one, but two parents that they have to get out of the house before they can properly say hello to each other. "THEY'RE ALMOST HERE!"

His words are confirmed by Natalie's car turning into the driveway. Stiles can see Lydia in the passenger's seat, her eyes already fixed on his bedroom window. When she sees him, she lets a slow smile spread across her face before her mother says something to her, and Lydia snaps her expression back into the proper position.

If it had been anybody else, they wouldn't be able to act well enough to keep themselves hidden. But Lydia Martin is a professional at what she does, and Stiles is already weird and fumbly enough that he's pretty sure the two of them can conceal anything.

When they had started sleeping together, neither of them had really worried about being able to hide it. It's been two years, nearly three, and aside from a few near misses that had more to do with  _logistics_ than failure to play their parts, Stiles and Lydia have managed to keep their secret well hidden. Which is why he takes exactly three minutes after Lydia arrives before he stumbles down the stairs, yawning hugely and immediately making his way over to the fridge.

"Stiles," says Natalie, "Lydia's back."

"Hey," he says to her, jerking his chin in her general vicinity as he scours the fridge for absolutely nothing. In reality, he's focusing on the brief snapshot he'd gotten of her as he'd walked down the stairs into the kitchen; the strawberry blond hair that falls down her back and the way her navy blue coat is pulled tight around her waist.

"Hi," she says in return, sounding bored. "So when's dinner?" Lydia adds to Natalie. "Do I have time to unpack?"

"Actually, it's ready now," replies Stiles' dad, pointedly shutting the fridge in Stiles' face. "Lasagna."

"I'll just go take off my coat," says Lydia, making to head up the stairs, but her mother grabs her shoulders and pulls her into a hug.

"Oh, you're not going anywhere," she croons in Lydia's ear. "My little girl is finally back from college! It's been a whole semester! I'm not letting you out of my sight  _once_."

Stiles can actually see the panic in Lydia's eyes as she glances over at him for one brief moment. He swallows hard and turns to his dad.

"I, uh, guess I'll set the table."

"I'll take Lydia's coat," says the sheriff. "I'll just put it in the front closet."

Natalie is still holding onto Lydia's arm as she ushers Lydia into the dining room. Stiles can hear them speaking quietly as he moves around the kitchen, pulling plates, knives, and forks out of the cabinets. Whenever he passes the doorway, he can see Lydia's eyes darting over to him, and he knows that her hands are curled into themselves under the table.

He is very used to  _wanting_ her, but never when she's right there, and he cannot recall a time before when he was this frustrated. He hasn't seen her since August. She didn't even come home for Thanksgiving. If he doesn't get his hands on Lydia in the next twenty minutes, he's going to create a small fire in their kitchen to distract their parents and then sneak Lydia outside under the guise that they were looking for a hose.

Before they'd started sleeping together, Lydia had been the crush that Stiles had never quite managed to grow out of who just  _happened_ to be the daughter of his step-mother. It never really felt like Natalie Martin was his mom, and it definitely never felt like Lydia was his sister. By the time their parents got married, they were fourteen-years-old and Stiles had already had a thing for Lydia since the third grade.

Which only served to mean that the girl he thought of when he jerked off was two doors down the hall. It didn't mean his crush suddenly stopped.

It kind of sucked until they were sixteen and Lydia had decided that she was done pretending not to notice the fact that Stiles bumped into a wall whenever Lydia walked down the hallway in a towel or slammed into a door whenever he was looking at her. After that, it had been a flurry of wanting, needing, and having. The latter of which was rudely interrupted when Lydia had gotten accepted to MIT and their sex life had been thrown violently out of the window.

Their parents can't know that they Skype every day and text each other constantly and that once Stiles fingered Lydia in the bathroom at her aunt and uncle's wedding, because they might not be actually related but for some reason that is totally beyond Stiles, people still expect them to feel like they are.

Well, they don't. They really, really don't.

Like,  _really_.

His dad actually bangs his fork on the table to show his enthusiasm, which is supposed to make them all laugh but only gets Natalie. Stiles sits down and his and Lydia's chairs are way too close to each other, and he doesn't think anything is ever going to be funny again because his dad is dishing out lasagna and Stiles can hear a hitch in Lydia's breath when his skin brushes against hers as he goes to pick up his cup.

"Fuck, I forgot the salad dressing," he says without further ado, and pushes his chair out from the table.

"Will you get me some water?" Lydia calls after him.

"Nope," replies Stiles.

"Dick," she grumbles as she pushes her chair back from the table and follows him into the kitchen.

He's already waiting for her with his back pressed against the fridge, where their parents can't see them. Lydia turns the corner, tilting her head at him as she takes in his body for the first time in months.

"Hey," Stiles offers meekly. Lydia lets out a relieved sigh before she walks straight up to Stiles and presses her lips against his. Immediately, he feels like he is somehow being sewn back together by her touch. Her fingers skate along his jaw, his wrists, his hips, and she leaves fire in her wake, burning away the time they spent apart.

"Hi," whispers Lydia, voice breathy as her lips brush over the shell of his ear. When she kisses him again, it is open mouthed and greedy and he think he might melt in the refrigerator that she has him pushed against. "I missed you."

Stiles grins cockily.

"Oh, I know."

She narrows her eyes at him, annoyed, and raises her eyebrows towards the general direction his jeans.

"I guess it doesn't really have to be said that you missed me."

He kisses her temple.

"I missed you, Lyds."

She smiles brilliantly, all the venom of their banter sliding easily off of her face as she raises herself up on her toes and kisses him once again.

"Ready to go back in there?"

He groans.

"How the hell are you going to shake your mom off?"

She pats his cheek condescendingly.

"If we have to, we can destroy her."

Stiles tilts his head.

"You've been watching Buffy The Vampire Slayer again, haven't you?"

Lydia allows him to press a kiss against her forehead before she exits the kitchen.

* * *

 

When Stiles gets out of the shower, Lydia is splayed out across his bed reading a book. He hovers by the door with his hand on the towel that is wrapped around his waist, eyes lingering on the shorts which read  _Stanford_ on the butt. His school.

"Is there a reason you're naked on my bed?" he asks, and Lydia looks up from the book, a smile playing at her lips.

"I'm not naked."

"That makes one of us."

She laughs through her nose, throwing the book to the side and sitting up on her knees, staring at him as if she's trying to decide when to pounce. He's almost driven to distraction when he realizes that he's never seen her in that bra before, and he's seen  _all_ her bras. She bought it for him.

Fuck, he loves this girl.

"Do you ever sleep in those?" Stiles asks, gesturing towards her shorts with his chin.

"What took you so long?"

"Uh, I was making shapes in my hair using my shampoo."

It almost breaks her into laughter, but when Lydia has an idea, she sticks to it. Slowly, she unfolds her limbs, getting off of the bed and advancing towards him.

"Your dad's at work."

"He is."

Stiles has no idea how he's got this much willpower when Lydia is right in front of him with a smirk that would suggest she has the physical ability to hold the entire world up on her shoulders. Maybe it's because they've been apart for so long. Maybe it's because they're home alone for the rest of the day and they suddenly, surprisingly, have been granted actual time to be together.

"And my mom mysteriously got called in to substitute at Beacon Hills High School."

Suspicion flashes across Stiles as Lydia begins leaving open mouthed kisses on his chest, standing on her tip-toes to reach his neck. She winds her fingers into his wet hair and  _tugs_ and Stiles can't help himself as he wraps his hands around her waist, pulling her closer.

"Is that a coincidence?"

"I'll give you a solid 'maybe.'"

He tilts his neck to the side as she nuzzles into his skin slightly, biting and sucking.

"Lydia, did you assault a teacher?"

"Would you have a problem with that if I had?"

Yep. He definitely has a hickey. Great.

"Eh," Stiles replies, slapping her hands away from his towel and clicking the lock to his bedroom shut. Lydia frowns up at him, annoyed that he's not playing the game her way, but he bends down and kisses her with his thumbs ghosting over the apples of her cheeks. Lydia pulls them back towards his bed and falls against the mattress, kissing him in a way that is more violent than he is used to.

He's definitely not complaining. Especially not when she slides her shorts down and kicks them onto the floor of Stiles' bedroom, and the radiant smile she offers Stiles is enough for him to know that he definitely doesn't need the towel anymore. He ditches it as he follows her onto his bed and braces himself above her, kissing her and trying not to moan too loudly at her wandering hands.

"Fuck, I missed you," she sighs. " _God_ , why aren't you going to school in Boston?"

"Why don't you move back home?" he asks rhetorically, unsnapping her bra.

"And give up MIT? Oh no. You're moving."

He lowers his mouth to her breast and watches her eyebrows squeeze together as he wraps his lips around her nipple before pausing to consider this out loud.

"In this hypothetical scenario, how would I explain to everybody that I was moving to Boston so that we never again have to go this long without fucking?"

"You're smart," Lydia says, grabbing his hair and pulling his head back up so that he's eye-level with her. "Figure it out."

He thinks he's actually going to die in that moment, so he decides to pay her back by pushing the material of her panties to the side and dipping his fingers inside of her. Lydia makes an involuntary noise of desperation that has Stiles straight-up leering at her in lieu of having to make fun of her for the noise.

But there's a part of it that's just not funny, because it means that nobody's been touching Lydia like Stiles does. Nobody's  _ever_ touched Lydia like Stiles gets to, and that hadn't changed even when they'd been going to school on opposite sides of America.

Stiles sucks his finger into his mouth and almost feels his knees buckle at the wave of familiarity that washes over him at her taste.

"Shit," he groans, making sure he's licked all of her off of his finger before he lets his hands drift back down her body, his lips following the quakes he makes with his fingers. He kneels at the edge of the bed and waits for Lydia there, nudging himself between her thighs as soon as she joins him. A whimper resounds through Lydia's throat at the first pass of Stiles' tongue, and he can't help the low whine that he releases into her.

When he looks up at her, she's got her head thrown back and is bracing herself against her palms, her bottom lip sucked into her mouth. He spends so much time on his knees for her that this position isn't new or even novel. But he feels it somewhere in his stomach, curling there low and desperate. From the red flush across her chest to the vulnerability of her squeezed-shut eyes, everything about this is making it slam into Stiles- the fact that this is the girl he's in love with.

Which absolutely does not mean he's not going to torture the fuck out of her.

"So," he says, looking up at her. "How's school going?"

Lydia lets out an impatient whinge when she realizes that he's not going to get her off until she starts talking.

"Fine," she says. "Whatever."

"Do you like your dorm?"

"It's  _fine_ , Stiles."

"What are you learning?"

She opens her eyes, peering exasperatedly down at him.

"Really?"

He kisses the inside of her knee, then her thigh.

"C'mon, Lyds. Tell me about what's been happening," he says softly. Then he dips down again.

"We had this, um, this-"

Stiles cranes his neck.

"Spit it out."

"We had an amateur recitation TA who was… who was… who was teaching a pathetic lecture on cholesterols, and he completely failed to mention there's-  _there, Stiles_ \- there a reason that excessive ah-ah-activity can cause myocardial infarctions."

He smirks.

"Myocardial infarctions, huh?"

Lydia takes his momentary distraction to mash her lips together, her eyes squeezed shut as Stiles slides a finger into her. She clenches around him immediately, her moan low, and he turns his mouth's attention to her clit.

When she speaks again, her voice is more determined than ever.

"I brought up fact that the only reason that the plaque builds up on arteries can sometimes be triggered by stress… oh,  _fuck,_ Stiles!"

"You said 'oh fuck, Stiles' in class?"

"I'm going to destroy you _."_

"Sure. Reciprocity is key to any healthy relationship."

She opens her eyes long enough to glare at him, but with red cheeks and a heaving chest, there's nothing about Lydia that is intimidating.

"If you don't make me come within the next three minutes, I'm going to do it myself," Lydia snaps. "And after a semester of getting myself off, I can promise you that I am not going to be in a giving mood if that has to happen."

He takes the challenge almost greedily, eating her out until she's got one hand in his hair, tugging at the still wet strands and chanting his name over and over again with a litany of swears. Stiles is feeling sloppy and loose by the time he hauls himself back onto the bed and meets Lydia's fervent kiss.

"How'd I do?" he asks, burying the words in her lips. Lydia pulls away, eyes lidded as she stares up at him, still breathless.

"Tell me what you want," she says in response.

He can hear the affection in her voice and it washes over him in a way that makes his heart stutter slightly.

"Really?"

"I missed you."

"I want you to fuck me."

A beam spreads across her face.

"I was actually hoping you would say that."

She crawls out from underneath his body and lowers herself onto him, not bothering with a condom. They haven't really used one since they started saying 'I love you' to each other. They'd lost their virginity to each other in Lydia's bed on a freezing cold December day, just after Christmas, and every time was supposed to be the last time. There never was a last time- not a real one, anyways.

Eventually they had stopped thinking it was wrong because nothing had ever felt quite so good and it didn't matter to either of them, not when they wanted it so badly.

Though, to be fair, after not seeing her for so long, Stiles suddenly feels ill prepared for sex with Lydia Martin. He isn't ready for the small, high pitched whines at the back of her throat and the way she feels clenching around him. He wants everything  _more_ \- closer and faster and harder, but he's going to lose it in two seconds flat because Lydia is circling her hips around his and has her hands on his shoulders, scratching him lightly with her fingernails.

When she'd been gone, it had been too easy to forget the reality of her.

"Feels so good, Lyds," he groans as she pants above him. Her nails scratch a bit harder. "Want you so bad."

"I want you too," she sighs. "Always."

He closes his eyes to the feeling of what they are doing and tries to forget that their 'always' is terrifyingly limited.

* * *

 

 

The truth is, Stiles doesn't know what would have happened if Scott hadn't started dating Allison Argent when they were sophomores. He likes to think that he and Lydia would have fallen in love regardless- likes to think that Lydia would, eventually, to be with him in every version of their lives. But he thinks back to the way their relationship was before Allison Argent moved to town, and Stiles can't help but be grateful that Scott randomly decided to fall in love with the new girl.

When the four of them go out to dinner together, they usually end up at the same diner every time, hunting down a booth tucked away in a corner so that they won't be bothered by the little kids who are bouncing on the plush red seats or the old men who order eight cups of coffee and spend the whole day reading a newspaper and working on the same piece of cherry pie.

As per usual, Allison and Scott are on one side of the booth, their bodies tipped towards each other, their hands always seeming to get tangled up underneath the table. They smile and giggle and generally act ridiculous, and it makes Stiles want to burst into flames. He and Lydia are an appropriate length apart, their bodies purposefully shifted towards their friends. Because appearing to have the same level of comfort with each other as Scott and Allison do would be nothing if not a dead give away.

Scott had always known Stiles had a crush on Lydia. He had probably  _assumed_ that it developed into full-out love. He will probably never know that Lydia reciprocates, and that some mornings Stiles comes downstairs for breakfast and neither of their parents are home and they can sit at the island and crunch on cereal and Lydia can wrestle her coffee out of Stiles' grip because she knows it makes him jittery and feels that it is her job to rejuvenate what has been lost to selective memory. He will probably never know all of the things that Stiles pretends when he is sitting across from Lydia, all of the futures he plans that will eventually come to fruition with someone else.

Keeping this whole thing from Scott is the hardest part of their whole relationship.

"And don't forget about dinner with my mom tomorrow night," Scott is saying to Allison, looking over at her with eyes so earnest that it almost feels intrusive to look at them. Next to Stiles, Lydia digs her fork through her salad and stabs a crouton particularly hard.

"I won't," Allison promises. "I'm spending the day with Lydia, but then I'll be right over."

Lydia looks up, confused.

"Did we make plans?"

"I just did," says Allison cheerfully. "I haven't seen you all of break, Lydia! Where have you been?"

"I haven't seen much of Stiles either," Scott says accusingly. "Are you two so busy going to battle that you keep forgetting to fight with anyone aside from each other?"

They all know that Stiles and Lydia's relationship hasn't been nearly as belligerent as it was in the past, which is why they're all able to it around this table, joking about it. When they had first started living together when they were fourteen, Stiles had been awestruck that his crush was anywhere near him, and Lydia had been annoyed that this kid's dad had managed to sweep her mom off of her feet. It had taken all of freshman year for Lydia to stop being annoyed at Stiles for it, and most of the summer afterwards had been spent bickering back and forth in a way that hadn't felt bad, for once. They spent a whole year wasting time, with Lydia trying too hard to hate Stiles and Stiles pretending to hate Lydia.

Then Allison had come along, and they started spending more time together, and that had resulted in an easy friendship beginning to develop between the two of them. Lydia would come home after school and plop onto the couch next to Stiles, watching whatever show he was streaming from his computer. Stiles was suddenly allowed to wander into her bedroom whenever he wanted. Their parents were  _delighted_ with the change.

One night, during Christmas vacation of junior year, Lydia got to pick the movie, and in the middle of Jane Eyre they found themselves arguing over Rochester's characterization- even then, Stiles knew Lydia was right- and then they were making out. After a few days of awkwardness, they decided to have sex. Then they decided to just keep having sex until they got sick of it.

So far, they haven't.

Stiles doesn't know exactly when Lydia had started falling in love with him, but he does know that he had noticed small things that hadn't seemed real. A brush of the hand, a glance that lingered way too long, a smile that was too intimate. And he hadn't complained when he crossed the line because the line had literally never been there for Stiles.

It's there for other people. It's there for their two best friends, which is why they sit across from them and don't say anything. They spend so much time not saying anything. Sometimes it makes Stiles want to punch a wall out.

"That's what we do," Lydia is responding. "Drive each other up the wall so that we can drive our parents up the wall."

"It's working," Stiles says bluntly. "But, naw, I've been researching different types of law I could go into."

"And I'm looking into adding another major, so I've been looking up requirements."

"Well," Allison says. "As  _academic_ as that is, I'm sure you can take one day off and hang out with your best friend from high school."

"It may be difficult," Lydia says. "But I'll see what I can do."

They're not exactly lying. They have been doing those things. But that's mostly to distract themselves while they wait for Natalie to leave the house- and Stiles is starting to realize, looking at all these variables compiling up at once, that there is no way they can keep this up forever.

Someday, the cards are going to fall.

Looking over at Lydia, he wonders where they're going to land, and what's going to be left when the two of them finally go up in smoke.

* * *

 

Lydia glares particularly hard at Stiles when he plops a santa hat on her head.

"Really?" she grumbles, but he just pats her head and moves to hand a hat to Natalie.

"It's Christmas!" he sing-songs. "Don't be such a candy-cane in the mud."

"Aaaand that's it," Lydia says. "You're done with puns for the day."

Stiles places his hands on his hips and scowls at her, which is probably marginally less intimidating when he's wearing R2D2 footie pajamas. Lydia sticks her tongue out at him and slides out of her armchair onto the floor, reaching for one of the neatly wrapped presents under the tree. She crosses her legs underneath her as she reads the name on the gift and tosses it over to Stiles' dad.

"Good arm," he says. Lydia smiles her thanks, gracefully extending an arm to grab another present.

"Heads up, bozo," she says before throwing it at Stiles. It clocks him on the head, and he flips her off.

"Play nice," says Natalie as she leans down to Lydia to kiss her on the cheek and hand her a tiny box. Lydia scrunches her nose playfully towards her mother, throwing Stiles a small smile when neither of their parents are looking.

He sits on the other side of the tree and tries not to reach for her, but it's still a little strange. He can remember the Lydia who had flounced grumpily into their living room in a silk robe and an equally satin camisole on their first Christmas together, when they'd barely been able to speak to each other because it was so strange to have to live in a house together. Now she's sitting across from him on the floor wearing thick socks, an MIT hoodie, and cotton shorts. He'd woken her up this morning by jumping on her bed until she tugged his leg and made him fall down, whispering "Merry Christmas" before she'd moved in to kiss him. Stiles wants this so bad. He wants Lydia in satin, Lydia in cotton, Lydia totally and completely naked. And he wants that for every Christmas in the foreseeable future.

He doesn't want to have to give this up in favor of someone else. He can't stop  _thinking_ about that, even as Lydia hands a gift with his name written in her handwriting.

"For me?" he says, and she rolls her eyes.

"No, it's for one of the other people named 'Stiles' who live in Beacon Hills."

"For me." He grins.

"Just open it." Stiles rips off the paper and casts it carelessly aside. There's a large white box, which he lifts the cover off of to reveal a smaller white box. When he looks up, Lydia straightens her expression into one of utter seriousness. "Is something the matter?"

"Should I even bother to keep going?" he asks flatly.

"Why do you two torture each other like this?" asks his dad, leaning forward in his armchair to give Natalie a kiss of thanks for the watch that she'd gotten him.

"Mostly because it's fun," Lydia says chirpily. "Is there another reason?"

Stiles has gotten five boxes deep and has finally revealed the Mets calendar that Lydia got him.

"Very personal," he says, clutching his heart. "Thank you."

"And thank you for my gift," she says, lifting the box of tampons with a bow stuck on them. "Very useful."

"You're welcome," replies Stiles, taking the bow off and plopping it in Lydia's hair.

"Have you ever thought about going into fashion?"

"Since I was a small child."

"Let's  _eat_ ," suggests Natalie, pushing up from her armchair and heading towards the kitchen. "Honey, could you come help me with the sticky buns?"

The sheriff gets up, brushing a hand through Stiles' hair as he goes. For a moment, the two of them sit alone on the floor with the sound of Christmas music crooning softly in the background.

"Sometimes I think we should have set up a different facade," Lydia admits, her voice muted.

"Sometimes I think we're killing them."

"I know."

He turns to look at her, tucking some hair behind her ear.

"It would kind of kill them either way though. Y'know?"

"Right," agrees Lydia. "This is the best option. Them never finding out."

They're quiet for a few moments, listening to their parents murmuring together in the kitchen.

"So," Stiles says, clapping his hands together and crawling a bit closer to Lydia. "What did you actually get me?"

She reaches into the pouch of her MIT hoodie and pulls out a box, pressing it into Stiles' hands.

"I want the box back."

"Shut up," he replies, kissing her knuckles as she pulls her hand away. He unwraps it so quickly that he's pretty sure he's going to get a paper cut, but when he lifts the cover, he finds a plastic hotel key. "What's this?"

"It's an old hotel key from our vacation to the Bahamas a few years back." He stares at her. "But it's symbolic of the reservation I made for next week."

"At a hotel?"

"I want to sleep next to you," she whispers, brushing her thumb over his palm. He curls his fingers towards hers. "At least once before I go back to school."

Stiles grins.

"Shit. Me too."

"So," Lydia says briskly. "I've told my mom that I'm sleeping over at Allison's, and you're going to say you're sleeping over at Scott's, and then we're going to have reasonably loud hotel sex and not have to worry about anybody walking in on us."

That sounds so amazing that Stiles feels like he's going to do something stupid like kiss her. Instead, he reaches into his pocket and pulls out his gift for her.

"Hope you like it."

"Is it a gift card?" she teases. He lets an offended look drift across his face before he remembers the time he got her furry handcuffs just so he could write a pun on the card: " _Our love shall chain us together forever_."

"Allison helped me pick it out."

Lydia rolls her eyes.

"Oh, well. In that case, I'll probably like it."

"Actually, yeah, that's gotta count for, like, thirty percent of the gift. I went through extra efforts to make sure you liked it. Gimme some points there."

Lydia's nails slide neatly under the tape and he doesn't understand why he feels so nervous.

"Um. Wow."

She lifts up the chain, her eyes soft as she stares at the delicate gold locket.

"Yeah but that's not the good part."

"This isn't the good part?"

He pretends that he doesn't see tears brimming in her eyes as he shakes his head.

"The locket is whatever. Look inside."

Lydia tilts her head to the side, looking at him in amazement as she shakes her head.

"Seriously?"

"Do it."

She cracks the locket open and bursts into laughter at the dick pic he'd left her inside.

"This is the  _classiest_ nude you've ever sent me."

"What about the time with the glasses?"

"Classier."

"It looked like Clark Kent!"

"No it didn't, sweetie."

His lower lip trembles.

"Wait, what?"

Lydia glances at the doorway, then dives forward and kisses him briefly on the lips.

"Thank you," she says, pulling back. "I love you."

"Don't touch me," he replies, voice anguished. Lydia sighs and starts to pull away, but he grasps her chin and kisses her. "Psych. Love you too."

As if either of them would ever doubt it.

* * *

 

Most nights during the semester, Stiles had ended up on the floor of Scott's bedroom with a video game controller in one hand and a Fanta in the other. The night had usually ended with Scott getting booty called from Allison and Lydia texting Stiles to tell him to go home so they can say goodnight to each other.

Tonight, Lydia is running up and down the halls of the house half-dressed while Stiles blares loud music from the speakers in his room.

"Have you seen my hairbrush?" she asks, not bothering to knock. When he looks up, he sees that she's wearing a black bra and a deep maroon skirt, zipped up to the smallest part of her hips.

Her hair is flowing freely down her back, and he takes a mental snapshot of it so that he can think about it when she's back at school in a week.

"You can just leave the door open at this point," he tells her from his bed. "This is literally the third time you've interrupted me."

"Interrupted you from what? This very time sensitive comic that's been out for the last forty years?"

"Wow, been saving that one all night?"

"I'm still almost positive you have the bra I'm looking for."

"What would I do with your bra?"

She pauses from his dresser, where her hands are sifting quickly through his stuff, and turns around to throw him a look.

"I know about your water balloon swings. Scott broke and told Allison."

"Damn it, Scott."

"I want my bra back, and be ready to go in fifteen minutes."

"You said that a half an hour ago!" he shouts after her as she walks back down the hallway to her room. "Who the fuck are you trying to impress?"

She pads back down the hallway slowly, pausing in his doorway with one eyebrow raised.

"Three guesses," Lydia says, leaning her head on his doorframe. "Because I'm nice."

He hides his smile with the comic book. When they meet each other in the front hall in fifteen minutes, he's still smiling. So is Lydia. She puts her coat on and lets her curls drop over the collar, ignoring the way Stiles' fingers brush against her open palm as he leans over her to get into the closet.

"Yes, we'll be home by one," Lydia says, condescending. "Don't worry, mom. Stiles is a great driver."

"The best," he says, twirling the keys around his index finger. They slide off and clatter to the floor. Lydia spares him one look of disdain before she turns back to her mother.

"Correction," she says. "Stiles is an okay driver."

He opens his mouth to object, but Lydia grabs him by the wrist and pulls on his arm until he follows after her in a manner that he is ashamed to say is almost obedient. Lydia hops into his jeep and Stiles turns the radio station to top 40s, just to piss her off. She flicks him in the head in complaint, but leaves her hand on his neck, stroking up and down slightly as he drives.

"I hate these things."

It's the first time he's spoken since he started driving, and he doesn't mean for the words to be so filled with venom. But Lydia laughs, rubbing her thumb lightly over his skin.

"Me too."

He glances over at her with surprise on his face, but Lydia is staring at the road.

"Lydia Martin hates going to parties?"

"Don't say my name like that," she says sharply.

His insides go cold.

"What?"

"Don't say my name like you aren't the person who knows me best in the world."

Her hands slide off his neck and fold together in her lap. For a moment, she looks small.

"You just… You've always liked parties, Lyds."

"I don't like pretending not to like you," she snaps. "And it's okay when we have time, but there's only a week left until you're on the opposite side of the country and I'm left pretending that I'm not in a relationship when I have been since I was sixteen."

He wraps his knuckles around the steering wheel, squeezing too hard.

"Okay," he says slowly. "Well I don't like constantly having to say 'step' when guys tell me that my sister is hot."

"Ew," replies Lydia.

"Yeah."

"So we skip the party," she decides. "Just… Drive."

"Where?"

"Not Danny's party."

"Oh, I hear they have great burgers at that place."

"Wow."

"Not funny?"

"Not remotely."

The street lamps cast a shadow of her nose, and for a moment he is so painfully endeared to her that it makes him want to spill all of his pieces onto the floor of his car, just so she can have them, and see them, and maybe pick them up.

"I had a plan, you know," he says, cringing even as he says it.

"A plan?"

"When I was seventeen, and you had just told me you loved me for the first time, I made up this… I don't know. Escape plan."

"For?"

His voice is too soft when he says, "For us."

"Oh." It comes out in a whoosh of air, harsh against the cool of the night. "Tell me about it."

He scratches a hand across his clean shaven jaw and slams it hard against the wheel.

"You don't want to know."

"I do," she says, and when her hand comes to rest on his fidgeting knee, it is so earnest that it breaks his resolve to keep anything from Lydia.

"We were gonna leave," he says, telling it to his windshield. "Just… get the fuck out. Go somewhere nobody actually knew we were supposed to be siblings. And I would never have to listen to anybody telling me that my sister is beautiful as if I didn't already look at you like you were beautiful since we were in the third freaking grade." Out of the corner of his eye, he catches her look down at her lap with a smile on her lips, but she doesn't say anything, and he goes on. "We were going to live together. Go to school close together- that makes sense. Get a dog. Get married. I would totally have taught you how to do laundry eventually."

"As if."

Stiles pulls over into the woods, allowing his jeep to stumble over the dirt paths. He pulls over when they're at the edge of town, killing the engine and unbuckling his seatbelt.

"I know it sounds crazy, but I can't… I can't actually imagine a future where I don't get to do that shit with you. And I don't wanna do it with anyone else."

"Tell me more about it," she presses, reaching over to take his hand.

"Um, you were gonna get a doctorate. I was gonna pick out the couch because I would probably spend more time on it. We were gonna elope because… well, there's pictures of us in our parents' wedding. That would be fucking weird."

Lydia makes a small noise of agreement.

"So this plan of yours."

"My ten year plan, yeah."

"How were we going to explain that to Scott and Allison? Our parents?" His eyebrows scrunch together as he stares at their entwined hands, not saying anything. "Oh," she says again, understanding. "For me?"

"Yeah," says Stiles gruffly. "Of course for you." Anxiety crawls up his throat as he waits for her to respond. "So. Yup. What do you think? You in?" he adds teasingly.

"This is without a doubt the stupidest plan you've ever had. Of course I'm in."

He squeezes her hand tightly, and Lydia squeezes back. For a moment, he feels like a kid again. Stiles kisses the inside of Lydia's wrist, smelling the perfume she'd sprayed there earlier.

"Why did you stop?" Lydia asks. "What happened?"

"I became embittered with age."

She tilts her head to the side, annoyed.

"Be serious."

Stiles' heart is beating too fast as he leans his head against the headrest and rocks it towards her.

"I realized that I love you too much to force you to live that kind of life," he says, trying to shrug it off.

"What if I want you to force it on me?"

"I can't do that to you."

"It's not your decision."

He starts to smile, slow and too small.

"That's the thing, Lyds," he says. "It sort of is."

* * *

 

 

They decide in bed, the night before, that Stiles isn't going to bring Lydia back to the airport.

"It would be too obvious," she had said, whispering it into his bare shoulder and kissing the freckled skin there.

He stands at the window to her bedroom and watches her mom's car fade into the distance.

If Lydia turns around, he doesn't see.


End file.
